| (19) |
 |
|
(11) |
EP 0 227 337 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
27.09.1989 Bulletin 1989/39 |
| (43) |
Date of publication A2: |
|
01.07.1987 Bulletin 1987/27 |
| (22) |
Date of filing: 01.12.1986 |
|
|
| (84) |
Designated Contracting States: |
|
DE FR IT |
| (30) |
Priority: |
19.12.1985 GB 8531295
|
| (71) |
Applicant: PILKINGTON PLC |
|
St. Helens,
Merseyside WA10 3TT (GB) |
|
| (72) |
Inventors: |
|
- Maltman, William Ramsey
St. Helens
Merseyside WA10 3JA (GB)
- Threlfall, Ian Michael
Wigan
Lancashire WN2 30F (GB)
|
| (74) |
Representative: Pendlebury, Anthony et al |
|
PAGE, WHITE & FARRER
54 Doughty Street
London WC1N 2LS
London WC1N 2LS (GB) |
|
| |
|
| (54) |
Process for manufacturing photochromic articles |
(57) A direct casting process for manufacturing a shaped synthetic plastic article, such
as an ophthalmic lens, which has photochromic properties, the process comprising incorporating
a photochromic spiro-oxazine compound into a mixture comprising a highly reactive
polyfunctional monomer and a low amount of a polymerisation catalyst, and curing the
composition in a mould to form the shaped synthetic plastic article.